We demonstrate two game theory-based programs for headsup limit and no-limit Texas Hold'em poker. The first player, GS3, is designed for playing limit Texas Hold'em, in which all bets are a fixed amount. The second player, Tartanian, is designed for the no-limit variant of the game, in which the amount bet can be any amount up to the number of chips the player has. Both GS3 and Tartanian are based on our potential-aware automated abstraction algorithm for identifying strategically similar situations in order to decrease the size of the game tree. Tartanian, in order to deal with the virtually infinite strategy space of no-limit poker, in addition uses a discretized betting model designed to capture the most important strategic choices in the game. The strategies for both players are computed using our improved version of Nesterov's excessive gap technique specialized for poker. In this demonstration, participants will be invited to play against both of the players, and ...